This invention relates to a prosthetic foot and, more particularly to a prosthetic foot which is characterized by the fact that it consists of cooperative forefoot and heel portions which, respectively, incorporate attachment, spring, arch and toe sections and attachment and heel sections.
The prior art relating to prosthetic feet is characterized by a prolixity equal only to the severity of the problem which arises out of the loss of such essential portions of the human body.
The prior art is replete with various types of mechanical devices purporting to solve the foot prosthesis problem. Typical of early devices is Lange 2,075,583, which incorporates a rubber form mounted in operative relationship with a rigid metallic core. Exemplary of the latest developments in the field is Poggi 4,645,509, which teaches a prosthetic foot incorporating a monolithic keel or beam of relatively massive proportions intended to react to the load of an amputee's body during walking, running, jumping, and the like and to release the resultant stored energy to create foot lift and thrust complementing the amputee's natural stride.
However, none of the prior art devices has been completely succesful because of the fact that the component parts of the prosthesis, as in Lange, are too heavy and too rigid or, as in Poggi, are too massive and monolithic to respond properly to the nuances of stress-response gradients characteristic of the human foot.
One of the primary factors which has inhibited the creation of a successful prosthetic foot has been the fixation of the prior art with the duplication of the structural aspects of the skeletal and muscular components of an actual human foot. In many instances, as exemplified by Poggi '509, mentioned hereinabove, even the toes of the foot are attempted to be duplicated by providing simulacra thereof. It is this fixation upon the mechanical elements of the human foot which has restricted the art to an attempt to duplicate the human foot components, a tendency which is particularly exemplified in Gajdos 3,335,428.